Chain-grate furnace.



E, BOUSSE. CHAIN GRATE FURNACE. APPLICATION FILED AUG. 21, 1905.

aianied; Apr. 5,

2 SHEETS-SHEET l may 77597 M Z W E. BOUSSE. CHAIN GRATE FURNACE APPLIOATION FILED AUG. 21, 1905.

2 SHEETS-S3111 2.

EMIL BOUSSE, 0F BERLIN, GERMANY.

CHAIN-GRATE FURNACE.

Specification of Letters Patent.

Patented Apr. 5, 1910.

Application filed August 21, 1905. Serial No. 275,179.

To all whom 'it may concern:

Be it known that I, EMIL BOUSSE, engineer, a subject of the German Emperor, and resident of Berlin, V. 15, Uhlandstrasse 53, Germany, have invented certain new and useful Improvements in Chain- Grate Furnaces. of which the following is a specification.

This invention relates to furnaces com- )rising an improved traveling chain grate or burning solid or liquid fuel.

Traveling chain grates have been previously constructed of a series of grate bars connected to an endless chain passing over rollers in such a manner that by the continuous travel of the chain through the furnace the grate bars have necessarily become inverted at the firebridge end, and have remained in this inverted position, that is, with their fuel-bearing surfaces facing downward, throughout the bottom or return run of the grate. Such grates have two drawbacks, first, the partially consumed fuel is thrown olf immediately on passing over the rear roller, and thus becomes mixed with the ashes similarly thrown elf at the same spot, with consequent loss of still useful fuel and also considerable loss of heating effect. The second drawback is that the fuel and ashes thrown off as aforesaid, accumulate in a place where such accumulation cannot remain long without great inconvenience in the operation of the-grate, and whence it can only be removed by the firemen with great diifieulty, because this accumulation is situated at a spot which is at least the entire length of the grate distant from the front ash-pit door so that it can be scarcely reached by the usual scraper-and then only with considerable exertion. This is more especially the case with internally fired steam boilers in which there is no space available for the provision of a rear ashpit.

Now the present invention has for its object to provide a traveling chain grate in which the grate bars do not become inverted but retain their normal horizontal upright position in travelingalongthe return runof the chain, so that the partially burned fuel with the ashes are not necessarily thrown olf at the rear=end=ofthe grate, but may remain on the grate until-discharged at any desired point, preferably at the front end of the grate close to the ashpit door in the stoke-hold. This improved construction has. many advantages: First, the partially consumed fuel is not thrown off at the rear end of the grate, but remains on the return run of the grate until it reaches the front end of the lower grate run. Second, the heat radiated from the burning fuel and glowing ash on the return run of the grate mav be utilized to heat a feed water heater or the like arranged over said return run.

Third, in a horizontal grate of this type. the

heat radiated from the return or lower run,

serves to heat the air supply to the underside of the outward or upper run of the grate. Fourth, the return run of the grate acts as its own conveyor for its ashes which instead of being dumped down in an almost inaccessible spot, are delivered into the ordi nary ashpit at the front of the grate whence the ashes can be ren'iovcd without extra trouble or exertion.

In describing this invention, the term grate bars is intended to include not only the actual fuel-bearing and fuel-burning grate bars for burning solid fuel. and troughs or like vessels for burning liquid fuel, but also any plates, bars and other parts which may be employed as supports or car riers for the actual fuel-bearing and fuelhurning parts.

In carrying out the present. invention the several grate bars as above defined. are so suspended from or between the devices eniployed for moving them progressively through the furnace, that the grate bars will have a constant tendency to assume a horizontal or approximately horizontal po sition, so that they will remain in their normal (fuel-bearing) position not only during horizontal movements but also during curved or inclined movements of the grate. The retention of the horizontal positionmay be attained either by suspending or pivoting each g 'ate bar so that it can freely oscillate in the vertical plane and have a constant tendency to assume the horizontal position by reason of its own weight or of a counterweight, or by causing the grate bars to be acted upon by spec they are constrained to maintain the. horizontal position Means are provided for tilting the grate bars for the purpose of throwing off the fuel or ashes at any point.

The air required for the combustion of the fuel on thograte is first heated by passing between the upper and lower runs of the grate for the purpose of obtaining a better utilization of the fire-gases and preventing ial guides by which the formation of soot. A feed-water heater or a. superheater may be put in between the said upper and lower runs of the chain grate. As moving devices there may be employed flat link chains, racks, screws or other suitable devices operated by machinery or by hand from any suitable point. The forward movement of the grate causes the fuel to be automatically and continuously fed upon the grate through an adjustable opening below the fuel hopper in the required or desired quantity.

' Tl furnace fitted with an endless traveling grate constructed according to the present invention.

In these drawings :F igure 1 is a vertical cross section through a pivoted grate bar comprising a number of parallel members; Fig. 2 is a vertical cross section through a pivoted grate bar constructed as a bucket for holding liquid fuel. Fig. 3 is an end view of a pivoted grate prism-shape. Fig. 4 is a vertical cross section through a pivoted grate bar comprising a number of transverse members. Fig. 5 is a vertical cross section through a pivoted grate bar for liquid fuel. Figs. 6 and 7 are respectively a part side elevation and part plan of a grate composed of interlocking comb-shaped bars. Fig. 8 is a vertical cross section through a furnace fitted with a horizontal grate constructed according to the present invention.

Throughout the figures, similar letters re fer to similar parts.

Referring to Fig. 8, each grate bar a is connected at its-ends eccentrically, by means of pivots Z) to two endless fiat link chains 0, whlch run over front and rear chain-wheels d and are, in the construction shown, adapted to be caused to travel by means of a hand lever e acting through the ratchetwheel gear Z the worm m and the wormwheel 0 keyed upon the axle of the front chain-wheel 0?. The grate bars a have projections 7 provided with rollers which run on horizontal upper and lower guide rails g and thus keep the bars a in a horizontal position. At the curve of the rear chain wheel, the guide rails g are replaced by ribs 12. on the chain-wheel. At the point where each grate bar leaves the lower guide rail at y, it tilts automatically on its eccentric pivot b, with the result that the fuel or ashes carried by said bar is caused to slide off therefrom. A ortion of the upper ide rail 9 is mount on short pivoted inks i and is connected to a handle is by operating which the said portion can be raised andlowered, so as to cause the grate bars traveling over said ortion to slant, whereby the air space of the grate may be enlarged and the air-supply be regulated. The

partially burned fuel and glowing ashes reie accompanying drawings illustrate a bar of triangular eeaesa 7 maining upon the bottom run of the grate I heat the incoming air on its way toward the upper part of the grate, and the heat set 1 free at the bottom is used for heating a feed water heater 1). The fuel is fed from the hopper 79 through the adjustable opening 9 and is conveyed to the tire automatically through the progressive movement of l the grate. The opening 9 may be enlarged or diminished by raising or lowering the slide 9 by any suitable means. The firel bridger is mounted on supporters s pivoted at t so that it can be operated by means of the rod u and handle u 'to uncover one or more of the grate bars and thereby increase the effective fire area of the grate.

The improved grate shown in Fig. 8 is constructed as a horizontal grate, but grates according to the present invention may also be constructed as vertical grates, inclined (grates, step-grates, double grates, and revolving-grates.

' I claim as new and desire to secure by 'Letters Patent is 1. In a furnace, an endless traveling chain grate, comprising in combination an endless chain, a pair of wheels having their axes arranged in the same horizontal plane, said wheelssupporting the chain, a series of fuel 9 bearing elements carried by said chain, and means for maintaining said elements in their normal upright fuel bearing position in their passage inward, downward, and outward.

2. In a furnace, an endless traveling chain grate, comprising in combination an endless chain, wheels for supporting each end of the endless chain, a series of fuel bearing elements, each supported by said chain,

i means for maintainingthe elements in their normal upright fuel bearing position on both the horizontal movements and one downward movement thereof, and means for causing each element to assume a vertical position at the other end of the movement.

3. In a furnace, an endless traveling chain grate comprising in combination an endless chain, a wheel for su porting each end of the endless chain, sai wheels being in the same horizontal plane, a series of grate bars carried by said chain, means for holding I said grate bars with their up er surface in the same relative position on both the hori I zontal portions of the chain and on that portion passing over one wheel, and means for allowing sald bars to assume a vertical position on that ortion of the chain which is passing over t e other wheel.

4. In a furnace an endless travelingchain Having now described my invention, what esaesa of the gratebars in the same relative position on both the horizontal portions of the.

chain and on the portion of said chain engaging with one of the wheels, and means for allowing the grate bars to tilt as they pass over the other wheel.

5. The combination of a furnace and an endless chain grate, said chain grate com prising an'endless chain, a wheel for supporting one end of the endless chain, said wheel being arranged within the furnace, a second wheel for supporting the other end of the chain arranged outside the furnace, said wheels being in the same horizontal plane, a series of grate bars carried by the chain, and a guide for holding the grate bars with their fuel bearing surfaces in the same relative position while said grate bars are in the furnace, said guide terminating adjacent the outer Wheel so as to permit the grate bars to tilt to free themselves of the ashes carried thereby.

6. The combination of a furnace and an endless chain grate, said chain grate comprising an endless chain, a wheel located within the furnace for supporting one end of the endless chain, and a wheel located outside the furnace for supporting the other end of the chain, a series of grate bars, horizontal pivots connecting said bars to the chain, said pivots extending at right angles to the direction of travel and passing through each grate bar to one side of the center thereof, rollers connected to the chain, tracks for supporting said rollers, said tracks having a vertically movable portion with means for operating said movable portion, and a guidefor holding the grate bars with their fuel bearing surfaces in the same relative position While in the furnace, said guide terminating adjacent the outer wheel 1 whereby the grate bars may tilt to discharge their contents.

7. The combination of a furnace and an endless chain grate, said chain grate comprisin an endless chain, a pair of wheels arranged in the same horizontal plane, one of the wheels being within the furnace and the other wheel being located outside the furnace, a pivoted fire bridge arranged over the inner wheel, means for moving said fire bridge, the chain passing over the wheels, a series of grate bars carried by said chain, and means for holdin the grate bars with their fuel bearing sur aces in the same rela tive position while in the furnace.

8. The combination of "a furnace and an endless chain grate, said chain grate comprisin an endless chain, a pair of Wheels arrange in the same horizontal plane, one of the wheels being Within the furnace and the other wheel outside the same, the endless chain passing over said wheels, a series of grate bars carried by said chain, means for holding said grate bars with their fuel hearing surfaces in the while in the furnace, and a heat receiving device located between the wheels and between the horizontal paths traveled by the chain.

In testimony whereof I have hereunto signed my name this 8th day. of August 1905, in the presence of two subscribing witnesses.

EMIL BOUSSE.

WVitnesses:

ADALBERT MILLER, WOLDEMAR HAUPT.

same relative position. 

